Process optimization for simultaneous production of phenolic acids and enzymes with high transfructosylation activity in cupuassu (Theobroma grandiflorum) residue by submerged fermentation with Aspergillus carbonarius.

Cupuassu (Theobroma grandiflorum) generates a large amount of waste, which can be better used to obtain products with high added value through biotechnological processes. Thus, the present study aimed to obtain optimized conditions for the simultaneous production of phenolic acids, invertases and transferases enzymes in cupuassu residue with Aspergillus carbonarius. The main methodologies used to select the variables that influence the system were a Plackett-Burman design, followed by a Central Composite Rotational Design. The optimal conditions were use of 17.3% sucrose, 5.1% residue and 4.6% yeast extract to produce 2204.89 ± 5.75 mg GAE/100 g, 39.84 ± 2.08 U/mL of hydrolytic activity, 168.09 ± 3.81 U/mL of transfructosylation activity and 4.23 ± 0.19 of transfructosylation and hydrolytic activity ratio. Among the phenolic acids identified by the UFLC-DAD system, there was an increase of 148.17% in gallic acid and 205.51% in protocatechuic acid. The antioxidant activities also showed changes after fermentation, with an increase of 350% for the ABTS assay, 51.97% for FRAP, 22.65% for ORAC and 16.03% for DPPH. To the best of our knowledge, this is the first time that cupuassu residue is fermented with Aspergillus carbonarius to obtain invertases and transferases enzymes and phenolic acids. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05418-z.

α-Amylase inhibition, cytotoxicity and influence of the in vitro gastrointestinal digestion on the bioaccessibility of phenolic compounds in the peel and seed of Theobroma grandiflorum.

The aim of this work was to evaluate the bioaccessibility, cytotoxicity, antioxidant and antidiabetic potential of peel and seeds of cupuassu (Theobroma grandiflorum). Thus, the extracts of cupuassu were evaluated for inhibition of α-amylase, cytotoxicity, and bioaccessibility after gastrointestinal digestion and probiotic fermentation (Lactobacillus delbrueckii, Lactobacillus jhonsoni, Lactobacillus rhamus and Bifidobacterium longum). Digestion increased concentrations of phenolics, showing bioaccessibility of up to 274.13% (total phenolics) and 1105.15% (ORAC). ß-carotene, quinic, tartaric, malic, citric, epicatechin, ethyl gallate, epigallocatechin gallate, gallic acid, pyrocatechol, vanillin, ramnetine were the main compounds while the epicatechin, ethyl gallate, gallic acid and pyrocatechol were the major effective phenolic compounds. The extracts did not show toxic effects and the cupuassu seeds showed 97% inhibition of α-amylase and 47.91% bioaccessibility of pyrocatechol. This study suggests that cupuassu extracts are sources of natural antioxidants with promising antidiabetic potential, and probiotics are able to increase phenolic compounds, responsible for health benefits.

Evaluation of bioactive compounds, phytochemicals profile and antioxidant potential of the aqueous and ethanolic extracts of some traditional fruit tree leaves used in Brazilian folk medicine.

The aim of this study was to analyze eight selected species of leaves, used in the traditional medicine of the Northeast region of Brazil obtained from several fruit trees (grageru, soursop, jambolanum, passion fruit, insulin, nogueira, pedra ume kaá and stévia), regarding their polyphenols contents and antioxidant activity. Condensed and hydrolysable tannins, phenolics and flavonoids contents were determined and the antioxidant activities measured by ABTS, FRAP and ORAC assays. Organic acids were analyzed by HPLC-DAD system. Phenolic compounds of aqueous and ethanolic extracts were determined by UHPLC-DAD-MS. The results revealed high contents of total phenolics (13.34 ± 0.19 - 127.65 ± 0.21 mg.g-1 of GAE:QE (2:1) of sample) and flavonoids (12.30 ± 0.42 - 71.79 ± 0.00 mg.g-1 QE of sample). The ABTS results exhibited extraordinary activity in the extracts (74.48 ± 6.23 - 1487.33 ± 2.67 µmol Trolox.g-1 of sample). Acids quinic, tartaric, citric, gallic, chlorogenic, p-coumaric, ferulic and vanillic along with naringenin, rutin, vanillin, catechin, epicatechin, kaempferol were the most important compounds. Thus, these leaves extracts may be considered as sources of phenolics compounds having a high potential as natural antioxidants. In addition, the polyphenols present in these leaves have many beneficial effects and can also be used in medicinal and nutraceuticals products with enhanced bioactivities.

In vitro gastrointestinal digestion and probiotics fermentation impact on bioaccessbility of phenolics compounds and antioxidant capacity of some native and exotic fruit residues with potential antidiabetic effects.

A bioaccessibility study on polyphenols, flavonoids and antioxidant capacity after the in vitro simulated digestion was evaluated for extract of fruit (caja-umbu, cashew apple, canafistula, cupuassu, soursop, manguba and strawberry) residues. The results show that ORAC assay presented a significant increase (p ≤ 0.05) in bioaccessibility varying from 35.99 ± 0.02% (caja-umbu residue) to 339.83 ± 0.06% (cupuassu residue) after the digestion process. Approximately 15.01 ± 1.54 to 237.77 ± 4.10% of phenolic compounds were bioaccessible after probiotics fermentation. The identification and quantification of phenolic compounds were performed through the UHPLC-QDa-MS system. Catechin and epicatechin were widely detected in all fruit residues. After the gastrointestinal digestion and probiotics fermentation the contents of simple phenolics and hydroxybenzoic acids increased. Also, the α-amylase inhibitory activity exhibited a maximum value of 98.66 ± 1.41% for soursop residue. To the best of our knowledge, for the first time, bioaccessibility study on caja-umbu, canafistula and manguba residues was performed in association with antidiabetic effects. The soursop residue presented the highest bioaccessibility and can be potentially explored for application in functional foods and pharmaceuticals. Therefore, the joint consumption of probiotics and phytochemicals are essential for the effective assimilation by the human organism.

Phytochemicals screening, antioxidant capacity and chemometric characterization of four edible flowers from Brazil.

Edible flowers are receiving renewed interest as potential sources of bioactive compounds. The present study aimed to investigate the presence of bioactive compounds and antioxidant activity of some exotic flowers present in Brazil such as Amaranthus hypochondriacus, Tropaeolum majus (red), Tropaeolum majus (orange) and Spilanthes oleracea L. The content of total phenolic compounds, flavonoids, condensed, hydrolysable tannins and antioxidante capacity were determined. The identification and quantification of the phenolic compounds was performed through the UHPLC-QDa-MS system. The compounds p-coumaric acid and ferulic acid were identified and quantified for the first time in all flowers. Tropaeolum majus (red) presented the hightest amounts of total phenolic compounds and hydrolysable tannins. Also, it presented the highest antioxidant capacity for ORAC and FRAP assays. Thus, this study showed the diversity and abudance of natural antioxidants present in edible flowers, which could be explored for application in functional foods and pharmaceuticals.

Evaluation of bioactive compounds potential and antioxidant activity of brown, green and red propolis from Brazilian northeast region.

The aim of the present study was to determine the contents of bioactive compounds present in brown, green and red species of propolis cultivated in the Brazilian northeast states of Alagoas and Sergipe. The contents of phenolic compounds, flavonoids and antioxidant activity (DPPH, ABTS+, FRAP, ORAC) were determined. Identification and quantification of phenolic and flavonoid compounds were performed by using UHPLC-QqQ-MS/MS system. The results revealed high contents of total phenolics and flavonoids. Among the three species, the antioxidant potential had higher capacity in the red propolis. The presence of some of bioactive compounds viz. acacetin, artepellin C, eriodictyol, gallic acid, isorhamnetin, protocatechuic acid, vanillin and vanillic acid in Brazilian red propolis is reported for the first time in this work. Positive correlation between total phenolics versus the FRAP and ORAC methods was established which led to conclusion that antioxidant activity of propolis is mainly due to its phenolic compounds.